Locking device

ABSTRACT

A locking device suitable for NID housing security. The device includes a slotted cylinder, a key and key tool. The slotted cylinder has a resistance component contained in the cylinder. The key is mateable with the slotted cylinder and is held in place by the force of the resistance component. The key head has a cavity therein of a complimentary shape to the key tool so that the tool may be used to turn the key for locking or unlocking. A cylindrical sleeve is used for additional security. The sleeve fits over the mated key and slotted cylinder to protect against release of the parts and may further provide a barrier to removal from a structure being locked. By use of different key head cavity shapes each subscriber may only access their own line in a NID.

CROSS REFERENCE TO PRIOR APPLICATIONS

[0001] This application is a continuation-in-part of U.S. Serial No.09/363/522 filed Jul. 29,1999, now pending.

FIELD OF THE INVENTION

[0002] The invention relates to locking devices, and more particularlyto locking devices for use with network interface units (NIDs).

BACKGROUND OF THE INVENTION

[0003] Network interface devices (NIDs) or Network Interface Units(NIUs) house telephone line junctions and terminals. As used herein, theterms NID and NIU are interchangeable. The NID may provide eitherresidential or commercial line access to one or more subscribers. TheNID is typically placed between the subscriber's wiring and the serviceprovider's subscriber loop.

[0004] Typically, the NID is sectioned for separate subscriber andservice provider access. Each subscriber line terminal is typicallycovered by a hinged plate. Subscribers or service providers can usuallyaccess their individual lines in the compartment by lifting the plate,thereby exposing the subscriber line terminal. In many configurations,the compartment for a loop junction is limited to service provideraccess.

[0005] In most NID configurations, the individual subscriber line accesscover plate is designed to be readily accessed. The line access coversare typically one inch wide and two inches in length, although there areknown variations to these designs. Many configurations of these coverscomprise a slot through which an apertured flange fixed to the NIDhousing may pass. A subscriber may place a small padlock through theaperture in the flange to prevent the cover from being lifted.

[0006] Unfortunately, present NID designs which enable easy access bysubscribers and service providers, also permit access by unauthorizedpersons. The relatively small sized padlocks used for this applicationare known to have poor tamper-resistant characteristics. Additionally,due to the size of the cover, small padlocks must be used which areoften difficult to use given dexterity limitations of individuals and/orthe environmental conditions (i.e. poor lighting) at the NID. Evenexpensive small locks having improved tamper-resistant features alsopresent similar problems. Additional problems result when a subscriberbreaks a key in the lock or is unable to use the key provided with thelock due to the poor quality of the lock and key assembly. Further,larger locks, such as those having a combination or traditionally-sizedkeys, are typically not an option due to the size and physicallimitations of the NID enclosure.

[0007] Consequently, line access in NIDs remains relatively poorlysecured thereby exposing the subscriber to potential costs related torepair, theft and damage, particularly for NIDs accommodating numeroussubscriber junctions.

[0008] Accordingly, there exists a need to economically and simplysecure line access in NID configurations, and the like. There exists aneed to provide a tamper-resistant solution that may be used in arelatively small area. There further exists a need for a device which iseasily secured and removed by an authorized user of an existing NIDcover configuration without affecting the operation of neighboringsubscriber covers and/or accesses. Additionally, there exists a need toprovide a device that locks a subscriber's line access cover uniquelyfrom other accesses on the same NID, thereby preventing one subscriberfrom accessing another's line on the same NID.

SUMMARY OF THE INVENTION

[0009] Embodiments of the invention provide a locking device that may beused to prevent a subscriber from accessing another subscriber's line onthe same NID.

[0010] The locking device includes a slotted cylinder having a firstend, a second end and a first slot. The first slot has a distal end anda proximate end. The slot's proximate end coincides with the cylinder'sfirst end and extends from the first cylinder end longitudinally andpartially toward the second cylinder end. The cylinder has a second slotextending from, and opened to, the first slot distal end at an angle tothe first slot. The cylinder has a resistance component contained in thecylinder at its second end. A key, mateable with the slotted cylinder,has a shaft with a key head at the first end of the shaft. A flangeextends from and at an angle to a second end of the shaft. The key headhas a cavity therein. The device also includes a key tool which ismateable with the key head cavity. The key may be inserted into theslotted cylinder and turned to lock it therein. The key tool is used torelease the key from the slotted cylinder.

[0011] A cylindrical sleeve may be utilized for additional security. Thesleeve has a first end, second end, first inner diameter, second innerdiameter, and a third inner diameter. The first inner diameter is largerthan the outer diameter of the slotted cylinder so that the slottedcylinder may fit in the sleeve. The first inner diameter extends fromthe first sleeve and to a length corresponding at least to the length ofthe slotted portion and the slotted cylinder. The sleeve's seconddiameter is larger than the key head so that the key head may fit atleast partially within the sleeve. The second inner diameter extendsfrom the second sleeve end to a length of at least about the key headlength. The third inner diameter is positioned between the first innerdiameter and the second inner diameter. The third inner diameter islarger than the key shaft diameter and smaller than the key head so thatthe sleeve cannot pass over the key head. A slot extending the length ofthe third inner diameter section and partially into the cylinder wallaccommodates the key flange when the key is placed in the sleeve.

[0012] By use of different key head cavity shapes each subscriber mayonly access their own line in a NID.

DESCRIPTION OF THE DRAWINGS

[0013] The invention is best understood from the following detaileddescription when read with the accompanying drawings.

[0014]FIG. 1A depicts a slotted cylinder according to an illustrativeembodiment of the invention.

[0015]FIG. 1B depicts a key according to an illustrative embodiment ofthe invention.

[0016]FIG. 1C depicts a key tool according to an illustrative embodimentof the invention.

[0017]FIG. 2A depicts a sleeve according to an illustrative embodimentof the invention.

[0018]FIG. 2B depicts a cross-sectional view of a middle section of asleeve according to an illustrative embodiment of the invention.

[0019]FIG. 3 depicts a slotted cylinder being engaged with a key in asleeve according to an illustrative embodiment of the invention.

[0020]FIG. 4 depicts a slotted cylinder being engaged with a key in asleeve in an aperture according to an illustrative embodiment of theinvention.

DETAILED DESCRIPTION OF THE INVENTION

[0021] Embodiments of the invention provide a locking device that may beused in conjunction with NIDs and may be manufactured using relativelyinexpensive materials.

[0022] FIGS. 1A-C depict an embodiment of the invention comprising aslotted cylinder 100 and a key 102. FIG. 1A depicts a slotted cylinder100. The slotted cylinder 100 has a first end 104, a second end 106 anda first slot 108. The first slot 108 has a distal end 110 and aproximate end 112. The slot's proximate end 112 coincides with thecylinder's first end 104. The slot 108 extends from the first cylinderend 104 longitudinally and partially toward the second cylinder end 106.The cylinder 100 has a second slot 114 extending from the first slotdistal end 110 at an angle 140 to the first slot 108. The second slot114 may be straight or arced. The cylinder 100 may be provided with aresistance component 116 which is contained in the cylinder 100 at itssecond end 106. Preferably the resistance component 116 is affixed tothe inside of the slotted cylinder second end 106.

[0023]FIG. 2A depicts the key 102. The key 102 has a shaft 118 with ahead 120 at a first end 122 of the shaft 118, and a flange 124 extendingfrom, and at an angle 142 to, a second end 126 of the shaft 118. The keyhead 120 has a cavity 128 operably mateable with a key tool 130. Forexample, the cavity may have a star or plus shape, into which acomplimentary-shaped tool may be inserted. Additional examples of cavityshapes include triangle, square, “H”, pentagon, and “T”.

[0024] The key tool 130 may have any overall shape that enables a userto grasp and rotate it when engaged with the key. FIG. 1C depicts anillustrative embodiment of the key tool 130 with a key tool head 136complimentary in shape to the cavity 128 shown in FIG. 1B. The key tool130 has a handle 132 used to turn the tool. A screwdriver-type handle inline with the key tool shaft 134 is a further example of a functionaldesign.

[0025] The key flange end is inserted into the first slot 108 of thecylinder at the cylinder's proximate end 112 until it contacts theresistance component 116. The key 102 is then moved an additional amounttoward the slot distal end 110 until it encounters and compresses theresistance component 116. Once compressed the resistance component 116provides a force on the key 102 in a direction longitudinally along thekey shaft 118 toward the slot proximate end 112.

[0026] The key tool 130 is then inserted into the key head cavity 128.Using the key tool 130, the key 102 is rotated around an axis defined bythe length of the shaft 118 so that the key flange 124 moves into thesecond slot 114, thereby locking the key 102 into the slotted cylinder100.

[0027] The resistance component 116 may be any structure that wouldprovide sufficient pressure on the key 102 so that the key 102 is notfree to slide out of the second slot 114. The resistance component 116may be, for example, a metal coil such as a spring, rubber stop,elastomeric polymer, pliable plastic or other elastic material.

[0028] A further embodiment of the invention is depicted in FIGS. 2A-Band FIG. 3. This embodiment includes a cylindrical sleeve 200 which mayprovide additional security. FIG. 2A depicts an embodiment of the sleeve200. The sleeve 200 has a first end 202 and a second end 204 and isdivided into at least three sections 206, 208 and 210. The first section206 has an inner diameter L₁ which is larger than the outer diameter ofthe slotted cylinder 100 so that the slotted cylinder 100 may fit intothe sleeve 200. The first section 206 extends from the first sleeve end202 to a length corresponding at least to the length of the slottedportion of the slotted cylinder 100. The second sleeve section 208 mayhave a diameter L₂ which is larger than the key head 120 so that the keyhead 120 may fit in the sleeve 200. Preferably the second section 208extends from the second sleeve end 204 to a length sufficient to coverkey 100 to the extent necessary to require the key tool 130 to disengageit from the slotted cylinder. The key tool 120 will generally benecessary for disengagement if the key head 120 is not protruding enoughfrom the sleeve 200 to grasp it firmly enough to turn the key 100. Thethird sleeve section 210 is between the first and second sleeve sections206, 208. The inner diameter L₃ of the third section is larger than thekey shaft diameter and smaller than the key head diameter. The thirdsection 210 need only be as long as is necessary for the section to havethe structural integrity necessary to provide the desired security. Toothin a third section 210 may weaken the device and not satisfactorilyprotect against tampering. As depicted in FIG. 2B, the third section 210may have a slot 212 extending along the length of the section and cutpartially into the cylinder wall to accommodate the key flange 124 whenthe key is positioned into the cylinder 100 through the sleeve 200. Theslot 212 is only necessary if the length of the flange 124 is greater orequal to the radius of the key head 120 or if additional security isdesired. The reason for this will become apparent when the operation ofthe sleeve is described below.

[0029] Operation of the sleeve 200 is depicted in FIG. 3. The key 102 isplaced, flange end first, into the sleeve 200 at the sleeve second end204. The slotted cylinder 100 is placed, first end 104 first, into thesleeve 200 at the sleeve first end 202. The key flange 124 is alignedwith the slot 212 in the sleeve wall of the third section 210, if such aslot exists, as it is put through the sleeve 200. The key flange 124 isalso aligned with the first slot 108 in the slotted cylinder 100 as thekey 102 enters the slotted cylinder 100. The key 102 is pushed into thesleeve 200 and the cylinder 100 until it meets the resistance component116. At that point the key 102 is pushed farther until the key flange124 reaches the second slot 114 and can be rotated so that the flange124 is engaged with the second slot 114. This leaves the key 102 engagedwith the slotted cylinder 100 with the sleeve 200 surrounding theengaged key and cylinder. In the embodiment depicted in FIG. 3, thediameter L₃ of the third sleeve section 210 is smaller than the key head120 or the slotted cylinder collar 220, or both so that the sleeve 200cannot be slid over the engaged key and cylinder. The key 102 is lockedinto the slotted cylinder 100 and may have the sleeve 200 over the keyhead 120 so that the key 102 cannot be turned without the key tool 130.

[0030]FIG. 4 depicts the key 102 and the slotted cylinder 100 being slidinto the sleeve 200. In a preferred embodiment, when the key 102 isengaged with the cylinder 100, the uncollared end of the sleeve 200abuts the collar 220 of the slotted cylinder 100, and the outer face ofthe key head 102 is nearly flush with the outer face of the collar 218.

[0031] As depicted in FIG. 4, the sleeve-covered lock 410 isparticularly useful in conjunction with a latch. Latch 400 may comprisetwo apertured parts, a tab 402 and a lid 404, having apertures 418 and416, respectively. The apertured tab 402 fits through the lid aperture416 so that the tab aperture 418 may accommodate the sleeve-covered lock410. When used with such a latch, the sleeve first end 202 and theslotted cylinder second end 106 may be fashioned with collars 218 and220, respectively, so that the sleeve-covered lock 410 cannot be pulledthrough the tab aperture 418. A comparable configuration may be used ona NID cover.

[0032] Although suitable for communication systems having NIDs, thelocking device is also usable in other devices, such as lockers, utilityboxes, tool boxes, protecting units, security systems and the like.

[0033] The sleeve 200 may have a collar 218 on at least one end. Thesleeve collar 218 provides a barrier so that the sleeve-covered lockcannot be slid through an aperture. As pictured in FIG. 3, the sleevecollar 218 is not necessary at the slotted cylinder end of the sleeve ifa collar 220 exists on the slotted cylinder 100. In the embodimentdepicted in FIG. 3, the slotted cylinder 100 fits into the sleeve 200only as far as the collar 220. Therefore, when the sleeve 200 is overthe engaged key 102 and slotted cylinder 100, there is a collar at eachend of the sleeve-covered lock to keep the device from sliding throughthe aperture 418.

[0034] In a further illustrative embodiment, such as depicted in FIG.2A, the sleeve 200 contains two collars 218 to keep the device fromsliding through the aperture. In this embodiment, the slotted cylinder100 can be placed entirely in the sleeve 200, providing additionalsecurity. The inner diameter L₃ of sleeve section 208 will keep theengaged key and slotted cylinder from sliding out of the sleeve 200.

[0035] The sleeve 200 may function without any collar if, in addition tothe slotted cylinder 100 having a collar 218, the key head 120 is largerthan the sleeve end 204 so that the sleeve 200 cannot slide over the key102 when the key 102 is locked into the slotted cylinder 100. The keyhead 120 would have to be larger than the aperture 418 through which thesleeve-covered lock is placed. Preferably the key head 120 is very thinso it could not be easily grasped and turned without a key tool 130. Athicker key head 120 could be used in this fashion if for example, itwas convex.

[0036] Advantageously, one or more parts of the locking device maycomprise plastic or other economical material. The locking device,however, may be made of any material that can be formed into the desiredparts and that exhibits the structural integrity necessary to providethe desired security. A further illustrative example of a locking devicematerial is metal.

[0037] While the invention has been described by illustrativeembodiments, additional advantages and modifications will occur to thoseskilled in the art. Therefore, the invention in its broader aspects isnot limited to specific details shown and described herein.Modifications, for example, to the shapes of the key, key tool, slottedcylinder and sleeve, and to the materials used to fabricate the device,may be made without departing from the spirit and scope of theinvention. Accordingly, it is intended that the invention not be limitedto the specific illustrative embodiments but be interpreted within thefull spirit and scope of the appended claims and their equivalents.

Claimed is:
 1. A locking device comprising: a slotted cylinder having afirst end, a second end and a first slot, the first slot having a distalend and a proximate end, the first slot's proximate end coinciding withthe cylinder's first end, the first slot extending from the firstcylinder end longitudinally and partially toward the second cylinderend, the cylinder having a second slot extending from and open to thefirst slot distal end at an angle to the first slot, the cylinder havinga resistance component contained in the cylinder at its second end; akey having a shaft, a head at a first end of the shaft, and a flangeextending from and at an angle to a second end of the shaft, the keyhead having a cavity wherein the key locks into the cylinder byinserting it into the cylinder with the flange aligned with the firstslot, moving the key toward the distal end of the first slot until itencounters and compresses the resistance component and is aligned withthe second slot, and rotating the key so that the flange enters thesecond slot; and a key tool mateable with the key head cavity to rotatethe key for locking and unlocking.
 2. The locking device of claim 1further comprising a cylindrical sleeve, the sleeve having a first end,second end, first inner diameter, second inner diameter, and third innerdiameter, the first inner diameter being larger than the outer diameterof the slotted cylinder so that the slotted cylinder may fit in thesleeve, the first inner diameter extending from the first sleeve end toa length corresponding at least to the length of the slotted portion ofthe slotted cylinder, the sleeve second diameter being larger than thekey head so that the key head may fit at least partially within thesleeve, the second inner diameter extending from the second sleeve endto a length of at least about the key head length, the third innerdiameter positioned between the first inner diameter and the secondinner diameter, the third inner diameter larger than the key shaftdiameter and smaller than the key head so that the sleeve cannot bepassed over the key head, a slot extending the length of the third innerdiameter section partially into the cylinder wall to accommodate the keyflange when the key is placed in the sleeve.
 3. The locking device ofclaim 2 wherein the sleeve further comprises a collar at one or moreends.
 4. The locking device of claim 1 wherein the slotted cylinder hasa collar at the slotted cylinder second end.
 5. The locking device ofclaim 1 wherein one or more parts of the locking device compriseplastic.
 6. The locking device of claim 1 wherein the resistancecomponent comprises a material selected from the group consisting ofpliable plastic, elastomeric polymer, rubber and coiled metal.
 7. Thelocking device of claim 1 wherein the second slot of the slottedcylinder is arc shaped.
 8. The locking device of claim 1 wherein the keyhead cavity has a shape selected from the group consisting of atriangle, square, “H”, pentagon, “T”, cross and plus.